[PATCH] iomap: Make sure iomap_end is called after iomap_begin

[Andreas Gruenbacher <agruenba@redhat.com>]

Make sure iomap_end is always called when iomap_begin succeeds: the
filesystem may take locks in iomap_begin and release them in iomap_end,
for example.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
---
 fs/iomap/apply.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/fs/iomap/apply.c b/fs/iomap/apply.c
index 76925b40b5fd..c00a14d825db 100644
--- a/fs/iomap/apply.c
+++ b/fs/iomap/apply.c
@@ -46,10 +46,10 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags,
 	ret = ops->iomap_begin(inode, pos, length, flags, &iomap, &srcmap);
 	if (ret)
 		return ret;
-	if (WARN_ON(iomap.offset > pos))
-		return -EIO;
-	if (WARN_ON(iomap.length == 0))
-		return -EIO;
+	if (WARN_ON(iomap.offset > pos) || WARN_ON(iomap.length == 0)) {
+		written = -EIO;
+		goto out;
+	}
 
 	trace_iomap_apply_dstmap(inode, &iomap);
 	if (srcmap.type != IOMAP_HOLE)
@@ -80,6 +80,7 @@ iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags,
 	written = actor(inode, pos, length, data, &iomap,
 			srcmap.type != IOMAP_HOLE ? &srcmap : &iomap);
 
+out:
 	/*
 	 * Now the data has been copied, commit the range we've copied.  This
 	 * should not fail unless the filesystem has had a fatal error.

base-commit: 97e0204907ac4c42c6e94ef466a047523f34b853
-- 
2.26.2